This required one of my more excessive setups. I taped my 50mm prime lens reversed onto onto the front of my 70-300mm lens. I then had to tape some aluminum foil around the two to act as a heat shield. I needed as much light as possible, so I positioned a 150W incandescent light bulb a few inches away from a $20 U.S. bill. I attached my gorillapod to my camera to help stabilize it, and then rocked it up and down to focus.

very nice macro shot.
wish you had shown something more "interesting" part of the currency bill. especially when the complete texts (Big text-United States or Small text-The United States of Am) are not entirely in focus.